1. Field of the Invention
The present invention relates generally to metalworking apparatuses and, more particularly, to deburring machines.
2. Description of the Related Art
In connection with the worldwide increase of continuous steel casting plants, the predominant use of oxygen cutting for subdividing or longitudinal dividing and the rationalization respectively improvement of existing plants, the mechanized or even automated deburring or debeading, i.e., the elimination of the oxygen cutting burr normally on the lower edges of slabs, blooms and billets or the elimination of oxygen cutting beads on the top edges of the same, if possible right after the oxy-cutting longitudinal or cross dividing is increasing in importance. Especially cost advantageous, safe, easy to maintain and easy to implant deburrers with a high deburring rate are indispensable for the high production of modern plants.
Meanwhile there are a big number of well working deburrers, but the cost, the deburring rates, the expense for maintenance, good installation positions (in the production line) and before all the danger of injury and high noise level leave much to be desired.
With all known designs in successful operations so far, the following deburring principles with the appertaining main elements the meanwhile complained deficiencies and disadvantages apply.
Deburring Principles:
The workpieces are lying stationary with their front or end oxygen cutting burr above the deburrer for deburring out of the workpiece and are deburred by being pushed by means of a roller table, pinch rollers or pushing drives.
The workpieces are lying stationary with their front or end oxygen cutting burr above the deburrer for deburring out of the workpiece and are deburred by shifting the deburrer or by rotation of its drum against the fixed workpiece.
The workpieces are moved on a roller table with working or transport speed, the front and the end oxygen cutting burr are knocked off from out of the workpiece by overtaking or counter rotation of a deburrer rotor.
For this the stationary or shifting deburrers of the first three systems are equipped with straight, horizontal scarfing bars or with side by side arranged, maybe as well with elastically lifting or lowering, squared or round shearing blocks.
The deburrers of the fourth system use for deburring little hammers fixed with movable joints distributed along and around a rotor, which stand up by centrifugal force at high numbers of rotation and thus knock off the oxygen cutting burr passing above into many small pieces.
A as far as well successful design of a deburrer differing further away from the above systems is a machine traveling with a feed speed longitudinally with the oxygen cutting burr, which presses a plate like shearing tool on a lever against the lower workpiece surface from below and knocks off or shears off the oxygen cutting burr by a pendulum type swinging to and of the lever horizontally. This design, predominantly used on stationary resting workpieces, can be used because of its limited size of the shearing tool only for limited production, and at that only under limited circumstances such as much time requirement, big space requirement and extreme installation cost.
The three at the present stage most successful deburrers are described in short as follows:
A stationary or shifting deburrer with a piston body out of which adjacent arranged, compressed air propelled pistons shift upward the shear caps which they carry and press them against the lower surface of the workpiece and shear off or push off the cutting oxygen burr relative to its material composition and temperature, when the deburrer or the workpiece are shifting. The main disadvantage of this deburrer is its limited or only complicated use for continuously moving workpieces, its many moving parts and the at times low deburring rate (below 99%), i.e., little rests of the cutting oxygen burr stay at the workpiece or they are only flipped up. As well little pieces of the cutting oxygen burr can stick between neighboring pistons and shear caps and reduce the efficiency of the deburrer very much. This well reduces the deburring rate. Accessibility, safety, availability and low operation noise belong to the advantages of this deburrer.
Stationary and with an exactly above it positioned workpiece works a drum deburrer or respectively rotation deburrer, on the drum of which ring-shaped or round but as well springingly shearing tools could be found adjacently side by side and distributed on the circumference. The drum is lifted hydraulically and rotated slowly, whereby the cutting oxygen burr exactly above is sheared or pushed off. The robust and powerful operation of this deburrer ensure safe working as well with bigger cutting oxygen burrs, but noise and time requirement (stand still and positioning) as well as bad deburring rates together with the high expenses are the disadvantages of this deburrer.
A tilting deburrer with straight all over shearing strips on front and end is the most simple and lowest cost design of a deburrer. Although at a particular tilting a shearing strip is pressed sincerely against the lower surface of the workpiece, the bad deburring rate at side way inclined, convex or concave lower surface and the indispensable forward/backward traveling of the workpiece are the unacceptably big disadvantages of this deburrer, even if the deburring forces and the working noise are kept low by an inclined, evenly, increasing by attaching shearing strip.
The without doubt most positive deburrer for a time independent, fast deburring of workpiece passing without stop, with the smallest space requirement in a roller table gap i.e., following a continuous casting plant is the rotation deburrer with a quickly rotating rotor equipped with hammers.
Of course power requirement and plant cost are very high, but inclined position of the workpiece, convex and concave lower surfaces and differences of moving speeds are no problems for this deburrer within limits, even if the distance to the lower surfaces is given with a tight tolerance.
But other problems are imminent instead. As the oxygen cutting beard is broken through by the many small hammers often and unevenly with high forces and great speeds a very great noise develops. The wear is disproportionately high and often the hammers are destroyed and more often burr pieces are flipped up and subsequently not eliminated.
The amount of maintenance is extremely high due to the exchange or replacement of the little hammers and the necessary disassembly of protection panels, especially since the latter must be fastened very carefully because of the burr pieces flying away with high energy. Otherwise bad injuries or damages are caused by metal pieces flying further away.
Much less noise and more safety has a deburrer which operates with slower, i.e., with roller table speed at maximum. For this a beam-like piston body, arranged below the workpiece and equipped with compressed air actuated deburring pistons, is shifted for deburring against the stationary or slowly moving oxygen cutting burr after being pressed against the lower surface for deburring to well the workpiece can be pushed with its oxygen cutting burr against the stationary deburrer and this happens twice per workpiece at each end out of the workpiece toward the respective end and further on. This way no metal pieces flying around dangerously, as well if no complicated protection cover is necessary, but the workpiece has to be traveled to and from, wasting time. and space. But with this design parts of the oxygen cutting burr are flipped up as well.
A mechanical scarfing deburrer for the elimination of oxygen cutting burrs and oxygen cutting beads after the thermochemical transversal or longitudinal dividing of steel workpieces like slabs, blooms and billets in hot or cold condition, stationary or moving on a roller table, can be generally stated as including a horizontally arranged deburrer drum or a deburrer drum segment supported on its horizontal axle stubs, or a deburrer plate slightly inclined against the horizontal plane and supported by is shaft slightly inclined to a vertical axis, rotating by means of an electric motor or hydraulic drive or driven by the moving workpiece via a drive lever and gear box, of which the bearings, the scarfing knifes holder, or the scarfing knifes themselves can be lifted in a spring buffer fashion, and of which the shell of the deburrer drum or of the deburrer drum segment has fully or partly surrounding scarfing knife spirals or of which the deburrer plate has on its surface spoke-like or eccentric spokes, rectangular or parallelogram arranged or scarfing knife strips, as well arranged as rectangular or parallelogram-like scarfing blocks or also round scarfing blades, whereby the scarfing knifes or scarfing blocks attack the oxygen cutting burr with an angle of approximately 10xc2x0 to 80xc2x0 to the latter and can scarf it off continuously or piece after piece. Accordingly the round scarfing block will only be applied with the quarter adjacent to the oxygen cutting burr to be scarfed off when scarfing the latter out of the lower surface of the workpiece.
A special notching wheel device is arranged close by or near the scarfing deburrer to notch cutting burrs consisting of tough material and rotates in a tilting notching lever supported underneath the cutting burr and consist of one or more step wheels beside a multi-edge chisel wheel which carry the latter and are rotated by friction of the workpiece or a special drive.
The notching lever rests with its step wheel end on a piston of a compressed air cylinder, which will be pressed down when rotating the step wheel and jumps up when passing the step.
In a disk roller table in between the disks, sleeves are clamped on, which deform the oxygen cutting burr to a maximum of 3 mm heights against the lower surface of the workpiece for better notching before deburring. The sleeves in conical design as well push over higher oxygen cutting burr of more than 10 mm on the one side, improve thus the notching and the interruption of the whole oxygen cutting burr for deburring. The sleeves can as well be equipped with chisel edges for direct notching of the oxygen cutting burr.
To scratch off smaller rests of the oxygen cutting burr flipped up by the deburrer, a spring scratcher device is applied, which consists of a flat spring or a spiral spring, a spring support and scratchers and can give way against the scratch direction or a rectangular angle or any similar.
A mechanical scarfing deburrer can additionally be characterized by the scarfing knifes winding around the deburrer drum fully or partly, once or several times, having even constant or uneven irregular distances between them in a way that the oxygen burr can enter in total width or length into the deburrer drum or into the deburrer plate without touching the scarfing knifes or the scarfing spokes and that these then could scarf the oxygen cutting burr overtaking or moving in opposite direction. The scarfing knife spirals could as well be arranged in opposite directions, i.e., crossing each other once or several times winding around the drum.
A mechanical scarfing deburrer can additionally be characterized by a so-called separating chisel similar to a piece of scarfing knife being arranged at the end of a scarfing knife spiral or scarfing knife spoke with an angle of 90xc2x0 to 150xc2x0 in order to subdivide the cut oxygen cutting burr before a complete scarfing.
A mechanical scarfing deburrer can additionally be characterized by the scarfing knife spirals or the scarfing knife spokes consisting of scarfing knife pieces which are pushed into swallow tail or T-grooves in the deburrer drum shell or into the surface of the deburring plate and which are 20 to 500 mm. long and showing a cross section like an inverted T or like a trapezoid or a combination of both. They are bent or twist over their length.
A mechanical deburrer can additionally be characterized by including a round scarfing block equipped with a chisel like horizontal edge in the round section for contacting the lower surface of the workpiece, above which in a short distance the scarfing block is formed as a multi-edge with vertical edges.
A mechanical deburrer can additionally be characterized by a round scarfing block being only working with one quarter of its round edge to produce the scarfing effect, because of the speed relations of the workpiece respectively the oxygen cutting burr passing speed to the deburrer plate rotating speed in the scarfing block area.
A mechanical deburrer can additionally be characterized by a deburring scarfing speed which is the difference between the necessary moving speed of the scarfing knife spiral or of the scarfing knife spokes and the specific moving speed of the oxygen cutting burr on slab, bloom or billet, i.e. between 3 to 150 m/min. This difference is as small as possible, namely only two to five times the moving speed of the oxygen cutting burr or the oxygen cutting beads to avoid noise and dangerously flying parts of burr, beads and tools.
A mechanical scarfing deburrer can additionally be characterized by the deburrer drum resting in two independently heights adjustable bearing blocks, which allows to equalize various inclinations of the scarfing deburrer drum at the lower surface of the workpiece, angled positions as well as height positions, with the bearing blocks being rotatable.
These height adjustable bearing blocks, at least one, are resting on spring-like pneumatic lifting cylinders, which lift the scarfing deburrer drum against the surface of slab, bloom and billet and press it on near to the oxygen cutting burr, and this right before or during the scarfing deburrer drum rotation.
A mechanical scarfing deburrer can additionally be characterized by a deburring lever bearing a deburrer drum segment with a deburrer knife spiral at its upper end, standing slightly inclined to the vertical axis below the workpiece in a bearing and being linked via a reduction gear with a driving lever on the same axle, which protrudes vertically into a roller table gap and has a rotatably supported roller at the level of the workpiece for pushing, shifting and down pressing of the driving lever. Thereby the oxygen cutting burr at the workpiece front edge is scarfed off.
In the same bearing block a second driving lever with a pulling load is arranged horizontally lying in front of the driving lever and is solidly connected with an equally rotating, inclined in front and above it arranged deburring lever and its scarfing knife spiral. Between the driving levers a spring pulling element is provided, which allows a horizontal position of the driving lever at a vertical position of the driving lever by the help of a pulling weight on the driving lever 1. Thus the driving lever can be pulled with its deburring lever underneath the workpiece, where it rolls along towards the end of the workpiece until it jumps up pulled by the spring and presents the deburrer lever and its scarfing knife spiral before the end burr and this is scarfed off using the energy of the onward. moving workpiece.
A mechanical scarfing deburrer can additionally be characterized by the scarfing knife or a part of it resting on at least two points if not over its total length on springs and balancing thus heights differences and inclined positions of the lower surface of the workpiece.
A mechanical scarfing deburrer can additionally be characterized by the fact that the axle stubs of the deburrer drum segment are arranged flattened and height adjustable in the segment levers corresponding to the front surface of the deburrer drum and sit on lifting cylinders for pressing against the lower workpiece surface.
A mechanical scarfing deburrer can additionally be characterized by a scarfing deburrer plate resting on axial and radial acting bearing blocks of which the supporting frame is sitting in a spring like fashion on pneumatic lifting cylinders, which can lift and press the scarfing deburrer plate with its rectangular, parallelogram-shaped or round scarfing blocks against the surface of the workpiece to be deburred near the oxygen cutting burr just before or while the scarfing deburrer plate is rotating.
A mechanical scarfing deburrer can additionally be characterized by a notching chisel for notching and therefore for piecewise scarfing off of an otherwise with soft material undetermined long scarfed-off oxygen cutting burr and that this notching chisel is supported in its middle and having anvil disks on a solid notching lever supported by a knocking cylinder underneath the traveling workpiece, until a sudden thrust of the knocking cylinder makes the notching lever and the notching edge thrust up.
The notching chisel has one or two anvil disks beside its edge which serve to avoid a notching into the lower surface of the workpiece beside the oxygen cutting burr. The anvil disks can be designed in a spiral shape with a sudden step, which rotate by friction and compress a compressed air cylinder or a spring by its spiral shape, which jump up when passing the step and effect a notching thrust at regular distances.
A mechanical scarfing deburrer can additionally be characterized by a burr scratcher which is applied to scratch off rests of oxygen cutting burr after deburring, pressed onto the workpiece in a spring-like fashion. The scratcher has a scratcher blade made of a spring blade bent forward in scratching direction on its end and bent backwards otherwise and consist of an inclined scratching block and a clamping pad with clamping bolts. The end of the scratcher blade serving as scratcher edge is hardened or reinforced with hard and wear respectively heat resistant edges and show from down to up in scratching direction by the inclination of the scratcher block.